Bucket for steam-turbines.



No. 835,370. PATENTED NOV. 6, 1906.l J. W. SMITH.

BUCKET FOR STEAM TURBINES.

APPLICATION FILED SEPT. 7.1905. I

2 SHEETS-SHEET 1.

ff I V \\\\\T IJ/N y @gli-117m i e I No. 835,370. PATENTED NGV. 6, 1906. J. W. SMTH.

BUCKET FOR STEAM TURBINBS.

APPLICATION FILED SEPT.7,1905.

2 sHBBTssHEET 2.

UNITED .STATES PATENT orrion .ioHN w. SMITH, or nais, PENNSYLVANIA, AssieNon To BALL viiNeiNi;

COMPANY, or vANiA. l. f

ERE, PENNSYLVANIA, A CORPOR A.'..`l( )N 0F PENNSYLD BUCKET Fon s'riEAM-'rumames.

lPatented. Nov'. 6,1906.

lo @ZZ whom it may concern:

Be it known that 1, JOHN W..SMrrn,a citizen of the United States, residing in Erie, county` of Erie, and State of Pennsylvania, have invented .certain newgand 'useful '1inprovements in Buckets Jrior Steam-Turbines, of which the following is a specification.

In buckets as hitherto used eddy-currents were setup by the steam or other elastic iiuid passingl from one side of the This is especially so bucket to 'the' other. when the peripheral s eed is comparatively low in comparison to t e jet velocity, as the centrifugal effect on small articles of steam causes it to be compresse This com ression in turn increases the density o the steam or elastic iiuid at one ortion of the 4bucket and decreases the density of the same at another portion of the bucket.

This irention relates to .buckets for steamturbines, and has for its object to provide a -bucketrthe use of which will obviate the objectionable features caused by' eddy-currents, as hereinabove set forth, and which absorb a certain amount of useful energy; and the invention has further'forits object to provide a4 double or triplex bucket which may be readily inserted and attached to the turbine-wheel and by means of which the main jet of. steam may be divided into several jets, each jet being so 'conducted as to bedevoid of eddy-currents.v For this purpose the invention consists of an improved bucket 'for steam-turbines which is formed by providing a turbinewheel grooves or channels 'and arranging division-Walls in respect to said grooves or channels so as to have the space between wall, so as togform several buckets, or arranging a division-wall in a bucket so as to.

forma bucket within a bucket.

vThe invention consists, further', in certain novel features and combinations of parts, 55

which will Abe 'more fully described hereinafter and iinally pointed out in the claims.

' In the accompanying drawings, Figure 1 represents a vertical longitudinal section through a series of buckets of aturbine-Wheel, 6o'v taken on line 1 1 of Fig. 2, showing the buckets provided with division-Walls secured to the turbine-wheel by rivets. Fig. 2 shows a planview of Fig. 1 as seen from line 2 2 of Fig. 1s Fig. 3 shows a vertical longitudinal 65.

section` showing a turbine-wheel providedwith division-walls which are retained by the turbine-wheel by. friction. Fig. lipshows a plan view of Fig. 3 as seen from line 4 4 of Fig. 3. Fig. 5 shows a slightly-modified 7cV being provided with flan es engaging-grooves l in the turbine-Wheel ;k an Fig. 9 shows a erspective view of a bucket unit shownin ig. 8g

8 as seen from line 9 9 of Fig. 8.

Similar letters of reference indicate corresponding parts throughout the drawings. Referring to the drawings, A represents- -the turbine-wheel, which is provided with. 85.

grooves or channels B, which maybe mor- .tised out of the turbine-wheel or made in any other suitable manner. These grooves or channels guide the steam and form the buckets, as shown by the twogrooves B' in the 9o right-hand side of Fig. 1.

The` material of the turbine-wheelremaining between each adjacent groove Vis sharpcned at its upper end, as `shown by C in Fig.

1, and the central part of this remaining wall 9 5. I C is provided with a circular cut-out "artDg In order tov revent 'the-formation o eddycurrents in t e groovesor channels B .during the passage of thesteam through the. same,

division-walls E are provided,..ea c h.having an exterior portion of the saine curvature .as

the circular'cut-out part-Dj VFach separate' division-wallE is also rovided'with a c'ircular cut-out part F oft e sainev curvature as its circular exterior, so thatf'when the; divi- '-ie5l sion-Walls are 'assembled eachengages the c ir-.. 7

6 as seen from line 7 7 of 7 5 .vision-wall inserted in the lirst.

cular cut-out part D of the wall C ofthe turbine-wheel A and also the circular cut-out part of the adjacent division-wall- Each di# vision-wall is provided at its lower part with an opening F, through which rivets G' pass, and which in passing through holes G of the turbine-wheel secure the division-walls to the turbinawheel.

flhedivisicri-walls E may be readily assembled and when once secured to the turbina wheeljcause the grooves B to form the buckets proper.

instead of the form shown in Fig. l the division-walls may be shaped so as to take the form shown in Fig. 3. In this case the material forming the walls between each sive bucket is provided with a rei: which is engaged by a division-ii all rt such a manner that the irictional contact is sulicient to prevent the division-wall from being thrown outbycentriiugal force during thev rotation of the Wheel. This modilied forni of division-wall does not require the use of rivets to secure them in position.

caseit is desired to Ahave the cross-section oi thev 'bucketlv proper ofVs'omewhat circular' shape the grooves forming the buckets in Fig. 3 Amay be mortised so as to have rounded corners l, as shown in Fig. 5.

improved division-walls besides perorming their function assuch maybe used as buckets as well. 'ln this case a divisionwall of iria-ller size is arranged in a division-wall nat the outer part oi' the inserted division wall serves as a division-walland the inner part ef the saine as the groove or channl, the

proper being formed by a second di- This are rangement is intended for comparatively large buckets, and by it the formation of eddy-currents is entirely prevented. One

forni of the embodiment of this-idea is shown' in Fig. 6, wherethe turbinewheel A -is provided with an 'annular main groove Maud in addition thereto with grooves M yand recesses M2, of somewhat lar er curvature, are ranged transversely therewith. In the forni shown in this figure the grooves'therrselves do not form thevbucketsfas they vdid in the fornissh'own in Figs. 1 to 5, nor are Walls-.provided separating one groove from the next adjacent. Instead of these bucket units are provided which consist of a separating wall membei*l K, being-'tapering at its upper end Kwand which has projecting dewnwardly therefrom circular memberso'rprojections K2, K3, and The lower ends oi. the Wallmemb'ers K engage .the recesses M2 of the turbine-wheel, v.which recesses are alsoen aged by flanges K5 'of the circular member Iby 't ga D'ement of which the units are securely lhe d in position. The lowerv part of the wall member K and the circularmember K5 abut snugly ,aga inst the shoulder portion A. ofthe turbine-Wheel A. When assembled, the cine joint 'en-v cular members K2 and K3 andthe separating wall members l form the buckets proper, the member K3 acting asa division-wall to this so-formed bucket. The circular members K3 and K, together :with the separating Wall members K, torni also a bucket proper of somewhat smaller size than the first-formed bucket, the inner wall of the members K3 acting as a guide for the steam and the outer' wall of the members K4 acting as a divisionwall. llence two buckets, .or' a duplex bucket, is provided, which is formed by the wall and circular members. The circular members arranged on the wall members constitute a bucket unit, which as such may be readily manufactured and readily inserted in the turbine-wheel. B y having 'each unit complete in itselr` the assembling in the Workshop is greatly facilitated. Instead of two buckets three or more may be as readily formed. Another form of bucket-unit construction is shown in. Fig; 8, in which case the turbine-A wheel is again provided with antannular main groove M and in addition thereto with grooves M and recesses M2, arranged trans'- versely thereto. These recesses areso arranged that the material ofthe turbinewheel renraining'between the same forms a slioulder portion A, having a dovetail portion m at its end. Inthe form shown in Fig. 8 the bucket units each consists of a separating wall member N, being tapering, its upper end n having upwardly-extending circularfinembers` N, N2, and N3, the circular member N y being set back from the'lower `end Nx of the wall member-N, so that the end of the wall member forms substantially a projection adapted to engage one of the recesses .M

loo..

The free or upper end of the circular memy ber N is provided with'a flange N4, which engages the other recess M2, the circular niember N itself littingsnugly against the shoulder portion A of the turbine-wheel. When the separate bucket units 'are assembled on the turbine-Wheel, the adjacentV wall'members N form, with the circular members N and .NZ a .bucket proper, vthe circular member' N acting as aguide for the steam and taking the place of the'groove in the form described in' connection with Fig. 1 and. the circular member N2 acting 'as aA division-wall. The cireularmembers N 2 and. N3, together. with the Wall members, form also a bucket 'properof somewhat smallerA size' -than the first- 'formed bucket, the inner wall of the circular "member 2 acting as a-v guide for, the steam and the outer Wall of the circular member N 3 acting as a division-Wall'. Hence two buckets, ora duplex bucket, is .provided and may be formed -by theassembling of the separate' units d escrioadj.A instead ofltwo `buckets three or more Lk'may .be as readily formed, depending on the size of the ybuckets desired. rFliese separate units maybe inanu lectured at a comparantively smali cost and in large uantities andimay be easily assem- If the circular Wall Kain the form shown in reaches its Greatest density.

Fig. 6 and the circular Wall N2 in the form shown in Fig. 8 be made detachable or omitted entirely, the duplex' bucketsdescribed l would thenbecome single buckets.

As the centrifugal force causes the partii cles of steam. in the buckets to be compressed and the density of the same increased, it is advisable to reduce the area of the bucket in cross-section at the point Where the steam This may be avoided ingarger buckets by dividing the steam into several streams, as when using duplex or triplex buckets, as hereinabove described, and in smaller'buckets by reducing the cross-sectional area at the point of greatest compression-thatis, not have the division-wal s concentric to the grooves or channels, but eccentric thereto, as shown by X in Figs. 2, 4*, and 7.

The construction shown is especially adapted for buckets of large dimensions, such as -are used on a modern-size machine designed for running With a vacuum where the volume of steam has been increased by expansion to a larger proportion. By the use of my improved division-walls eddy-currents aire completely done away with, and hence no useful energy absorbedjwhereby the efficiencyof the machine is reduced'. l l

Having thus described my invention, I claim as new and desire. to secure by Letters Patent- .y

1. Aturbine-Wheel having mortised U- shaped grooves or channels, and divisionwallsforming buckets with said grooves or channels.

2. A turbine-Wheel having mortised U- shaped grooves or channels, and 'detachable division-walls forming buckets with said grooves or channels.

3 A turbine-Wheel having grooves or channels, division-walls Jforming buckets With'the grooves or channels, and division-Walls arranged in relation to said rst-named division-wall, so. as to form buckets therewith.

4. A turbine-Wheel havin an annular 'groove and recesses transverse y thereto, and bucket units in said groove vadapted to engage the recesses, each consisting ,of circular members and a separating Wall member.

5. A turbine-Wheel havin an annular groove and recesses transverse y thereto, and bucket units in said groove adapted to 'engage the recesses, each consisting of' circular members and a separating Wall member` taperingat its upper end.

6. Abucket unit, consisting o'r` a separating Wall member and'circular members thereon.

7. A bucket unit, consisting of a separat-I ing wall member, tapering at its upper end,

and circular members thereon. l, 8. A bucket unit, consisting of a separating Wall member and members integral therewith of substantially circular curvature.

9. A turbine-Wheel having grooves or channels, and a plurality of division-Walls substantially concentric to each other, the largest forming buckets with the grooves or-channels, While the others-form buckets Within buckets. v

In testimon that I claim the foregoing as my invention have signed my name in presence of two subscribin witnesses. l tIOHN W. SMITH.

Witnesses:

F. H. ScHUTn, J. A. FRITZ. 

